Jabir said to me, "Your cousin came to me," referring to Hasan bin Muhammad bin al-Hanafiyyah, "and asked, 'How is the bath from major ritual impurity performed?'I replied, 'The Messenger of Allah ﷺ used to take three handfuls of water and pour them over his head, then pour water over the rest of his body.'Hasan said to me, 'But I am a man with thick hair.'I answered, 'The Prophet ﷺ had even thicker hair than you.'"In another narration, the Prophet ﷺ would pour water over his head three times.
قال لي جابر: وأتاني ابن عمك- يعرض بالحسن بن محمد بن الحنيفية- قال: كيف الغسل من الجنابة؟ فقلت: كان رسول الله ﷺ يأخذ ثلاثة أكف ويفيضها على رأسه، ثم يفيض على سائر جسده، فقال لي الحسن: إني رجل كثير الشعر، فقلت: كان النبي ﷺ أكثر منك شعرا. وفي رواية: كان النبي ﷺ يفرغ على رأسه ثلاثا.
Bukhari included it in the chapter on ghusl (256) through the route of Mamar bin Yahya bin Sam, who said, "Abu Jafar narrated it to me" with this wording. Muslim also related it in the chapter on menstruation (329) through another route, from Jafar, from his father (who is Muhammad, known as Baqir), from Jabir, and in it, "Whenever the Messenger of Allah performed ghusl from janaba, he would pour three handfuls of water over his head."Hasan bin Muhammad (bin Hanafiyya) said to him, "My hair is thick." Jabir said, "I said to him, 'Nephew, the Messenger of Allah's hair was thicker than yours and finer.'"In Bukhari (255), through the route of Mukhawwal bin Rashid, from Muhammad bin Ali, from Jabir, "The Prophet used to pour water over his head three times."And in another version in Bukhari (252), Muhammad Baqir said, "He and his father were with Jabir, and there were some people present, and they asked him about ghusl." He said, "A saa of water is enough for you." A man said, "It is not enough for me." Jabir said, "It was enough for one who had thicker hair than you and was better than you." Then he led us in prayer wearing a single garment.In another version in Muslim (328), through the route of Abu Sufyan from Jabir, the delegation of Thaqif asked the Prophet, saying, "Our land is a cold land, so how should we perform ghusl?" He said, "As for me, I pour water over my head three times."